Means for preventing racing in screw-propelled vessels.



G. SOLLITT.

LED VESSELS.

" nuns FOR PREVENTING RACING m SCREW PBo PEL (Application filed Jan. 14, 1902.) (No Model.) ZSheata-Sheat I.

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No. 7|6,|23. Patented Dec. l6, I902. a. SDLLITT MEANS F 0R PREVENTING RACING IN SCREW PRUPELLED YESSELS.

(Application filed Jan. 14, 1902.)

(No Model.) 2 Sheets-sheaf 2.

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ATENT FFICE GEORGE SOLLITT, OF HASTINGS, NEW ZEALAND.

MEANS FOR PREVENTING RACING IN SCREVl-PROPELLED VESSELS.

SPECIFICATION forming part of Letters Patent No. 716,123, dated December 16, 1902. Application filed January 14,1902. Serial No. 89,746. (No model.)

To all whom it may concern:

Be it known that I, GEORGE SOLLITT, a subject of the King of Great Britain, residing at Hastings, Hawkes Bay, New Zealand, have invented new and useful Improvements in Means for Preventing Racing in Screw-Propelled Vessels; and I do hereby declare the following to be a full, clear, and exact description of the same.

racing, upon emersion or partial emersion of the propeller, thus avoiding the serious risks attending such action.

According to my improved method the sup ply of steam to the engines is controlled by means of the compression and rarefaction of air produced by the up-and-down motion of The lower portion of the cylinder is connected with the external water in such a manner that it shall find access to the under side of the piston,

the rise and fall of such piston being governed by the difierent and varying depths of immersion of the vessels hull. The appara-. tus for carrying out this operation consists of a cylinder that is closed at the bottom end and open at the top and which is placed above the propeller-shaft, preferably as far aft in the vessel as therunl of her stern will permit. This cylinder is in communication with the external Water by means of pipes provided with suitable shut-off or regulating valves. Mounted above the cylinder isanother cylinder or extension that is provided with a piston and piston -rod, which passes through stuffing-boxes on the top of a dome-shaped upper end of the top cylinder. The piston-rod is connected to counterweights by means of cords passing over pulleys on able manner, so that by its movement up and down the valve may be caused to open or close and thus shut off or open the steamsupply.

In the accompanying drawings, Figure 1 is a side elevation of the appliances employed for carrying out the object of this invention.- Fig. 2 is an end elevation of the same. Fig. 3 is a sectional end elevation of the same. Fig. 4 is a detail of the means for operating the throttle-valve.

a is the propeller-shaft, above which is mounted upon a suitable stand I) the short cylinder 0. This cylinder is closed at the bottom and is open at the top and has opening into it from each side the pipes d, that lead downward though the hull e of the vessel and are formed with open months, so that the outside water may enter therein. These pipes are provided with the shut-01f valves f for regulating the amount of water to be admitted to the cylinder 0, and consequently the pressure of water within the cylinder. Secured upon the top end of the cylinder 0 is another cylinder g, whose bottom end is open, so as to form a continuation of the cylinder 0. The upper end of the top cylinder is closed by a dome-shaped cover h, provided with stuffing-boxes, through which passes the piston-rod i, connected to the piston j, fitting within the cylinder g. The faces of the piston j are preferably concave, while its circumference is formed with a groove, which, Withthe inner face of the cylinder, forms an annular chamber or space, as shown in Fig. 3, which may be supplied with oil, which will serve the double purpose of lubricating the piston and preventing the passage of air through the cylinder. Suitable cocks k may be arranged on the side of the cylinder for feeding oil to the annular space or for drawing ofi any water or air that might find ingress to the cylinder.

The top end of the piston-rod t'is provided with a cross-head Z, to which are attached cords m, passing over pulleys it, supported by brackets 0 on the top end of the cylinder g. These cords have attached to their loose ends the counterweights p, that rest in suitable guides in the side of the cylinder and serve to counterbalance the weight of the piston and piston-rod.

Leading from the top end of the cylinder g is a pipe 1*, that leads to the engine-room, where it is connected to the bottom end of a small cylinder a, that is provided with a piston and piston-rod. The top end of the piston-rod of this cylinder is connected by means of the lever twith a toothed wheel 10, that gears with a smaller toothed wheel upon the spindle of a throttle-valve 'u, controlling the passage of steam through the steam-pipe w, that leads to the engines.

The action of the apparatus is as follows: Assuming the vessel to be on an even keel and the screw-propeller wholly immersed, the pistonj then occupies the upper end of its cylinder, owing to the pressure of water beneath that enters through the pipes d. When, however, the stern of the vessel lifts out of the Water and the propeller becomes partially emersed, the water will escape from the cylinder, and the pressure beneath the piston is removed, so that it will fall or be drawn down, when, owing to the expansion of the air thus obtained above the piston, and consequently within the pipe 1", the piston within the cylinder 8 will be drawn down and the spur-wheel it turned so as to close the throttle-valve 2), its turning motion being assisted by means of the weighted arm 00, attached to it. The supply of steam will thus be shut off or reduced, so that the speed of the engines will be decreased while the propeller is out of the water. Upon the vessel regaining its natural level water will rise once more within the cylinder 9 and force upward the pistonj and cause the air within the air-piper to be compressed,so as to force up the piston within the cylindersand open the valve '0 again. The counterweights 19 will assist the pistonj in its upward movement.

In practice it will be found advisable to have an independent pressure of air within the air piper and the space above the piston j of about two pounds to the square inch, so as to provide for expansion and compression by the downward and upward movement of the piston.

What I claim as my invention, and desire to secure by Letters Patent, is

1. In appliances for preventing racing in screw-propelled vessels, an air-tight cylinder fitted vertically within the vessel, a chamber beneath the cylinder in communication therewith, pipes leading from the chamber through the hull of the vessel, a piston within the cylinder provided with a piston-rod projecting through the top end of the same and counterweights attached to the piston-rod, in combination with means whereby the up-and-down movement of the piston may be caused to open and close the valve of the steam-pipe leading to the engines, as herein set forth.

2. In appliances for preventing racing in screw-propelled vessels, in combination, an air-tight cylinder fitted vertically within the vessel, a chamber beneath the cylinder communicating therewith, pipes leading from the chamber through the hull of the vessel, a piston within the cylinder provided with a piston-rod projecting through the top end of the cylinder, counterweights attached to the piston-rod, an auxiliary air-tight cylinder provided with a piston and piston-rod connected to gearing adapted to open and close the valve of the steam-pipe leading to the engines, and a pipe connection leading from the top end of the main cylinder to the bottom end of the auxiliary cylinder, as herein specified.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

GEORGE SOLLITT. Witnesses:

F. S. RoULsToN, H. HUMPHRIES. 

